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Terminal 1,3-buadiene (Bd) functional polymers are stoichiometrically reacted with living anionic polymers in a monoaddition manner in THF at −78 °C, but neither polymerization nor oligomerization occurs under the conditions. By utilizing this reactive but non-polymerizable character of the Bd function toward living anionic polymers, a variety of block copolymers and regular and asymmetric star-branched polymers were successfully synthesized. In these syntheses, the terminal Bd functionalized polymers work effectively as reactive building blocks, namely polymeric efficient linking agents, to construct such architectural polymers. Since all the polymer segments used for the syntheses were derived from living anionic polymers and the linking reactions quantitatively proceeded, the architectural polymers herein synthesized were well-defined in structure and were precisely controlled in chain length. A new protocol based on iterative approach by repeating a two reaction sequence involving linking reaction and re-introduction of Bd group was proposed and developed to successively synthesize asymmetric star-branched polymers up to a 6-arm ABCDEF type. The terminal Bd functionalized polymers were readily and quantitatively converted to anhydride or diepoxide functionalized polymers by Diels–Alder or oxidation reactions. Because of their high reactive termini, the resulting polymers are also usable as reactive building blocks to synthesize the core-functionalized star-branched polymers with carboxylic acids or hydroxyl groups. The reactions between terminal anhydride and amine functionalized polymers were carried out in bulk at 180 °C to examine the synthetic possibility of star-branched polymers under such conditions.

The synthesis of an array of ω- or α,ω-multifunctional polyisobutylenes (PIBs) with 2, 4, and 8 benzyl bromide moieties has been demonstrated by an iterative divergent methodology using ω- or α,ω-functional PIBs with allyl halide moiety (moieties) as starting materials. The multifunctional PIBs were successfully applied for the synthesis of A2B, A4B, and A8B asymmetric star polymers as well as A2BA2, A4BA4, and A8BA8 pompom polymers where A and B were poly(methyl methacrylate) (PMMA) and PIB segments, respectively. The synthetic method involved the coupling reaction of living PMMA with multifunctional PIBs in tetrahydrofuran at −40 °C. The coupling efficiencies were virtually quantitative in all cases. The well-defined structures of the resulting branched polymers were confirmed by size exclusion chromatography−right angle laser light scattering and 1H NMR analyses. The microphase-separated morphologies of all AnBAn type pompom polymers were supported by differential scanning calorimetry. The stress−strai...

By combining two living polymerizations, anionic and ring opening (ROP), the following novel multiblock multicomponent linear and miktoarm star (micro-star) polymer/polypeptide hybrids (macromolecular chimeras) were synthesized: Linear, PBLL-b-PBLG-b-PS-b-PBLG-b-PBLL; 3micro-stars, (PS)2(PBLG or PBLL), (PS)(PI)(PBLG or PBLL); 4micro-stars, (PS)2[P(alpha-MeS)](PBLG or PBLL), (PS)2(PBLG or PBLL)2 [PS, polystyrene; PI, polyisoprene; P(alpha-MeS), poly(alpha-methylstyrene); PBLG, poly(gamma-benzyl-L-glutamate); and PBLL, poly(-tert-butyloxycarbonyl-L-lysine)]. The procedure involves (a) the synthesis of end- or in-chain amino-functionalized polymers, by anionic polymerization high vacuum techniques and appropriate linking chemistry and (b) the use of the amino groups for the ROP of alpha-amino acid carboxyanhydrides (NCAs). Molecular characterization revealed the high molecular weight and compositional homogeneity of the macromolecular chimeras prepared. The success of the synthesis was based mainly on the high vacuum techniques used for the ROP of NCAs, ensuring the avoidance of unwanted polymerization mechanisms and termination reactions.

The subject of this review is to introduce a novel iterative methodology based on living anionic polymerization using specially designed 1,1-diphenylethylene (DPE) derivatives recently developed for the synthesis of well-defined many armed star-branched polymers with same or chemically different arm segments. The methodology basically involves only two sets of the following reaction conditions for the entire iterative synthetic sequence: (a) a linking reaction of a living anionic polymer with a DPE-chain-functionalized polymer, and (b) an in situ reaction of a DPE-functionalized agent with the anion generated by the linking reaction to reintroduce the DPE functionality usable for the next reaction. The number of arms to be linked by each stage of the iteration depends on the starting core and DPE-functionalized agents and can dramatically increase by the agent of choice. New functional asymmetric star-branched polymers involving conductive and rigid rod-like poly(acetylene) segment(s) have been synthesized by the methodology using the intermediate polymer anions produced by the linking reaction as macroinitiators to polymerize 4-methylphenyl vinyl sulfoxide, followed by thermal treatment of the resulting star-branched polymers.

Background and Aim: Little is known about the clinical efficacy of cotherapy of ecabet sodium, a mucoprotective agent, and a histamine H2-receptor antagonist. The aim of the present study was to assess its additive benefit in combination with cimetidine for gastric ulcer. Methods: In this prospective randomized study, after gastric ulcer was confirmed by endoscopy, 200 patients in 47 hospitals received either ecabet sodium 1 g b.i.d and cimetidine 400 mg b.i.d. (EC), or cimetidine 400 mg b.i.d. alone (C) for 8 weeks. Healing was examined by endoscopy at 4 and 8 weeks. Results: Of the intention-to-treat (ITT) population (EC, 103; C, 97), 181 patients comprised the per protocol (PP) analysis (EC, 93; C, 88). At 4 weeks, healing rates were significantly higher in the EC group (60%) than in the C group (36%) ( p

A case of metastatic tumor of root of the tongue from the liver which occurred in a 59-year-old man is reported in this paper in conjunction with a relevant literature review. The patient's primary complaint on admission was hemosputum. Total removal of the tumor occupying the root of the tongue was carried out under general anesthesia. The histopathological findings revealed that the tumor was a metastasis of hepatocellular carcinoma. A review of the literature revealed very few reports of pharyngeal metastases derived from hepatocellular carcinoma.

Little is known about the clinical efficacy of co-therapy of enprostil, a prostaglandin E2 analogue, with a histamine H2-receptor antagonist. We aimed to assess the additive benefit of enprostil in combination with cimetidine for treating gastric ulcer in a prospective multicenter randomized controlled trial.In 43 hospitals 171 intention-to-treat (ITT) patients, diagnosed as having gastric ulcer by endoscopy, were randomly allocated to receive either enprostil 25microg b.i.d. and cimetidine 400mg b.i.d. (Group E=85), or cimetidine 400mg b.i.d. alone (Group C=86) for 8 weeks. Healing was examined by endoscopy at 4 and 8 weeks.Per protocol (PP) analysis comprised 166 patients (E=82, C=84). Despite no significant advantage at 4 weeks (E=55.3%, C=42.2%), the combination yielded higher healing rates at 8 weeks by ITT (E=89.4%, C=68.6%; p0.001) and PP analysis (E=92.7%, C=70.2%; p0.001). Symptom relief rates [E, C] at 2, 4, and 8 weeks were [80.2%, 68.3%] (not significant), [97.4%, 88.3%] (p0.05), and [95.6%, 87.0%] (p0.05), respectively. Significant advantage was observed in the patients aged 40 or older, with solitary ulcer (5mm in diameter), and without smoking or drinking habits. No adverse effects were critical.Enprostil safely and significantly augmented gastric ulcer healing and symptom relief by cimetidine.

HLA antigens, hepatitis B virus (HBV)-associated antigens and lymphocyte subsets in liver tissue from 35 patients with HBs antigenemia were studied using an immunoperoxidase double staining method and immunoelectron microscopy in order to clarify the immune mechanism of hepatocyte lysis in type B hepatitis. Immune light and electron microscopy using monoclonal antibodies to lymphocyte subsets revealed that infiltrating lymphocytes in the areas of piecemeal necrosis and focal necrosis were predominantly CD8-positive, showing direct contact with hepatocytes. In contrast, CD4(+) cells were infrequently observed in necrotizing inflammatory lesions. HLA-A,B,C antigens were mainly found on hepatocytes in areas of piecemeal necrosis and focal necrosis, in association with CD8(+) lymphocyte infiltration. HLA-DR antigens were demonstrated on a few hepatocytes in the same lesions. In cases of CAH with serum HBeAg positive, HLA-A,B,C, antigens and HBV antigens simultaneously demonstrated on the same hepatocytes. Especially, hepatocytes expressing both HLA-A,B,C antigen and HBsAg on the plasma membrane showed direct contact with CD8(+)lymphocytes. This finding fulfilled the morphological requirements for HBsAg as a target antigen. On the other hand, HBcAg was hardly demonstrated in the liver cell membrane but was demonstrated mainly in the cytoplasm. Compared with the nuclear localization of HBcAg in cases of NSR, cytoplasmic localization of this antigen may be associated with membranous expression of new antigens induced by HBV infection.

急性白血病に合併した真菌性敗血症による多発肝膿瘍の2剖検例を報告する.急性白血病に対する化学療法施行中,末梢血中の白血球数の減少とともに発熱が出現し,続いて低アルブミン血症,黄疸がみられ,肝機能検査では血清アルブミン値低下,III清ビリルビン,アルカリフォスファターゼ値の上昇がみられたが,血清トランスアミナーゼ値は正常もしくは軽度上昇したにすぎなかった.出血傾向や感染にもとづく全身状態の急速な悪化のために,各種画像診断は施行できず,黄疸の原因は病理解剖時まで不明であった.病理解剖により,1例はカンジダ敗血症による肝膿瘍,他の1例はムコール敗血症に由来する肝膿瘍が明らかにされ,黄疸は真菌性肝膿瘍によるものと考えられた.近年,抗腫瘍剤,副腎皮質ステロイドの使用増加に伴い,深在性真菌症も増加してきており,急性白血病患者の発熱,黄疸に際しては,真菌性肝膿瘍をも考慮すべきであると思われた.